(a) Field of the Invention
The present invention relates to a slide rail structure for a window blind, and more particularly to a slide rail structure which is provided with at least one extensible rail set, at least one pulley set, and a plurality of top brackets to achieve effects of an easy and quick assembly, a stable positioning, a smooth sliding, and being delicate and pretty, thereby being applied to all kinds of slide rails for window blinds or similar structures.
(b) Description of the Prior Art
A conventional slide rail structure for a window blind includes primarily a plurality of rail sets which are installed on a top edge of a window. A lower edge of each rail set is provided respectively with a plurality of parallel sliding slots, for sheathing sliding rods which are used to suspend a body of window blind. In addition, a top edge of each of the aforementioned rail sets is provided with a plurality of locking slots, and a positioning set is constituted by positioning units which are fixed at two sides of the top edge of window to suspend the rail sets. The positioning unit further includes a positioning plate and a plurality of positioning blocks which are serially installed on the positioning plate, and a bottom end of the positioning block is provided with a locking part which is latched with the locking slot of rail set, so as to be associated with an implementation for suspending the body of a multi-layer window blind, by adjusting an amount of the locking part of positioning block and of the rail set. Although the slide rail structure for the window blind is provided with the function of suspending the body of multi-layer window blind, the rail is in a fixed design; therefore, a length of the entire structure is fixed, and the structure cannot be extended for use. Moreover, as there are too many locking positions in the entire structure, it will cause an inconvenience to implementation personnel while working on site, and thus waste a labor time. On the other hand, if the rail is configured as usual, into two slide rails which are assembled together and can be loosely extended with respect to each other, as a connection surface of the two rails is formed with a stage-like drop, a pulley which slides in the rail will not slide smoothly, or will be even jammed. Furthermore, an end side of each slide rail should be sheathed with a side cover to prevent the pulley from sliding out. Accordingly, the conventional rail structure still cannot meet a user's requirement in a practical application.